Flexible electro-active lens

ABSTRACT

A lens including a flexible refractive optic having a fixed refractive index, an electro-active element embedded within the flexible refractive optic, wherein the electro-active element has an alterable refractive index, and a controller electrically connected to the electro-active element wherein when power is applied thereto the refractive index of the electro-active element is altered.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/017,858, now U.S. Pat. No. 9,155,614, filed Jan. 22, 2008, whichclaims priority to U.S. Provisional Application No. 60/881,514, filedJan. 22, 2007, and to U.S. Provisional Application No. 60/960,607, filedOct. 5, 2007; all of which are incorporated herein by reference in theirentireties. This application is also related to U.S. Publication No. US2006/0095128-Al, published May 4, 2006; U.S. Provisional Application No.60/636,490, filed Dec. 17, 2004; U.S. Provisional Application No.60/623,947, filed Nov. 2, 2004; U.S. Provisional Application No.60/659,431, filed Mar. 9, 2005; U.S. Provisional Application No.60/669,403, filed Apr. 8, 2005; and U.S. Provisional Application No.60/960,607, filed Oct. 5, 2007; all of which are incorporated herein byreference in their entirety.

BACKGROUND

Intraocular lenses (IOLs) may be used within the surface of an eye forrestoring vision function, for example, via implant for patients ofcataract surgery. IOLs include monofocal lenses, which provide a singlefocus or single optical power, multifocal lenses, which provide multiplefocus or optical power, and accommodating lenses, which adjust the focusof a lens.

The IOL may be inserted in a folded state through a small 3 mm or lessincision of the eye. A syringe-like device having a piston may be usedto help apply and position the IOL into the capsular bag whichpreviously housed the removed natural crystalline lens. Once in the eye,the IOL maybe unfolded to its natural state. When the incision size forinserting an IOL into the eye is larger than 2-3 mm undesired astigmaticchanges of the cornea occur. Therefore ophthalmologists prefer to usethe smallest incision possible for inserting an IOL into the eye.Therefore this makes a flexible and foldable IOL practically anecessity.

Corneal inlays, cortical on-lays and single vision and bifocal contactlenses are also used to correct vision of the patient. In many casesthese are worn to correct for the patients distance and near visionneeds. Each of these is a very thin optic and requires curvature whenapplied on or in the eye.

Presently all known electro-active elements within an electro-activelens are made of rigid materials. In a certain previous embodiment ofthe inventors with regards to an electro-active contact lens anelectro-active element is housed within a flexible outer host material.However, the electro-active element is rigid and therefore may add somethickness to the contact lens.

SUMMARY OF THE INVENTION

Embodiments of the invention provide a flexible electro-active lensincluding a flexible refractive optic having a fixed refractive index,an electro-active element embedded within the flexible refractive optic,wherein the electro-active element has an alterable refractive index,and a controller electrically connected to the electro-active elementwherein when power is applied thereto the refractive index of theelectro-active element is altered. The flexible electro-active lens mayinclude one or more intraocular lenses, intraocular optics, spectaclelenses, contact lenses, corneal onlays, corneal inlays, and inter-ocularlenses.

DESCRIPTION OF THE DRAWINGS

A specific embodiment of the present invention will be described withreference to the following drawings, wherein:

FIG. 1 shows a flexible electro-active lens 2 in a folded state having aflexible housing and an rigid electro-active element in accordance withan embodiment of the invention;

FIG. 2A shows a flexible electro-active lens 2 in a folded state havinga flexible housing and a flexible electro-active element in accordancewith an embodiment of the invention;

FIG. 2B shows an electro-active lens 2 in an unfolded state having arigid housing and a flexible electro-active element in accordance withan embodiment of the invention;

FIG. 3A and FIG. 3B show an expanded and collapsed view, respectively,of a flexible electro-active lens 2 in an unfolded state having asurface relief diffractive pattern and a liquid crystal layer inaccordance with an embodiment of the invention;

FIG. 4A shows the flexible electro-active lens 2 in a folded statehaving a plurality of electro-active elements in accordance with anembodiment of the invention;

FIG. 4B shows the plurality of electro-active elements of FIG. 4A inaccordance with an embodiment of the invention;

FIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D, each show a front view of theflexible electro-active lens 2 having an electro-active element, inaccordance with an embodiment of the invention;

FIG. 6 shows encyclorotation of the eyes;

FIG. 7A and FIG. 7B each show a front view of the flexibleelectro-active lens 2 having an axis A and a cross sectional view of theflexible electro-active lens 2 taken at the axis A, in accordance withan embodiment of the invention; and

FIG. 8A, FIG. 8B, and FIG. 8C, each show the placement of theelectro-active lens 2 in an eye having different pupil size, inaccordance with an embodiment of the invention.

The method and apparatus of the present invention will be betterunderstood by reference to the following detailed description ofspecific embodiments and the attached figures which exemplify suchembodiments.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

The following preferred embodiments as exemplified by the drawings isillustrative of the invention and is not intended to limit the inventionas encompassed by the claims of this application.

A flexible electro-active lens 2 is illustrated in FIG. 1, FIG. 2A, FIG.2B, FIG. 3A, FIG. 3B, FIG. 4A, FIG. 4B, FIG. 5A, FIG. 5B, FIG. 5C, FIG.5D, FIG. 7A, and FIG. 7B according to different embodiments of thepresent invention. Although the electro-active lens is described,embodiments of the invention may be used as other lenses including, forexample, intraocular lenses, spectacle lenses, contact lenses, cornealonlays, corneal inlays, and inter-ocular lenses.

The electro-active element (e.g., described in reference to FIG. 1, FIG.2A, FIG. 2B, FIG. 4A, FIG. 4B, FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D, FIG.7A, and FIG. 7B), the liquid crystal layer (e.g., described in referenceto FIG. 4A and FIG. 4B), and a pixilated element may all be used todescribe materials having optical properties that may be altered byelectrical control. Although the alterable properties described hereintypically include refractive index and optical power, embodiments of theinvention may include electro-active lens 2 having other alterableproperties, such as for example, prismatic power, tinting, and opacity.The properties of the materials may be controlled electrically and/oroptically.

Terms such as “rigid”, “hard”, “inflexible”, “inelastic” and/or “notfoldable”, may all be used to describe a material or structure adaptedfor resisting structural or shape changes when a force above apredetermined threshold is applied. Terms such as “bendable”, “soft”,“flexible”, “elastic”, and/or “foldable”, may all be used to describe amaterial or structure adapted for changing structure or shape when aforce above the predetermined threshold is applied. Terms such as“unfolded”, “unfolded state”, “natural”, “flat”, and/or “relaxed”, mayall be used to describe a material or structure in a relatively highentropy state (e.g., as shown in FIG. 2B, FIG. 3A, FIG. 3B, FIG. 4B,FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D, FIG. 7A, and FIG. 7B). Terms such as“folded”, “folded state”, “curved”, and/or “bended”, may all be used todescribe a material or structure in a relatively low entropy state(e.g., as shown in FIG. 1, FIG. 2A, and FIG. 4A).

FIG. 1 shows a flexible electro-active lens 2 in a folded state having aflexible housing 4 and a rigid electro-active element embedded in thehousing. The rigid electro-active element 6 typically does not bend whenthe electro-active lens is folded. The rigid element may protectelements contained therein from compression, bending due to expansion orcontraction of materials, or other forces internal or external to theelement. The rigid element may include a rigid encasing and may haveelastic components, such as electro-active material. Typically the rigidelement may be spaced from the peripheral edge of the electro-activelens to allow the folding thereof.

FIG. 2A shows a flexible electro-active lens 2 in a folded state havinga flexible housing 4 and a flexible electro-active element 6 embedded inthe housing. Since the flexible electro-active element typically doesnot prevent the electro-active lens from bending, the electro-activeelement may extend radially farther toward the peripheral edge of theelectro-active lens where the folding typically occurs. For example,when the electro-active lens is folded, the flexible electro-activeelement may curve along the peripheral bend of the folded lens. Theflexible electro-active lens may be embedded in a rigid housing for useas a spectacle lens.

FIG. 2B shows an electro-active lens 2 in an unfolded state having arigid housing 4 and a flexible electro-active element 6 embedded in thehousing. For example, the element may be minimally rigid for protectingelements contained therein from some internal or external forces and/orfor biasing the electro-active lens toward the unfolded state. Theelectro-active element may be less flexible than the electro-activelens.

In reference to the flexible housing 4 in FIG. 1 and FIG. 2A, and inreference to the flexible electro-active element 6 in FIG. 2A and FIG.2B, each of the flexible elements of the electro-active lens 2 may beadapted for moving between a folded state and an unfolded state. Each ofthe flexible housing and/or the flexible electro-active may be composedof a flexible material, such as, for example, polysulphones,polyetherimides, and/or other thermo-plastic materials. Polysulphonesare a class of transparent dielectric polymers that are stable over awide temperature range (e.g., from −110° C. to +150° C.) and pH range(e.g., from 2 to 13). Polysulphones are highly resistant to mineralacids, alkali, electrolytes, acids, and bases. Polysulphones are highlyresistant to oxidizing agents such as bleaches, which, when for example,the electro-active lens is used as a contact lens, may be applied to theflexible housing for lens cleaning.

Referring again to FIG. 1, FIG. 2A, and FIG. 2B, the housing may or maynot have optical power. A housing with optical power may have a fixedoptical power and may be a refractive or diffractive lens (e.g., shownin FIG. 3A and FIG. 3B). For example, a housing without optical powermay not focus light.

The electro-active element 6 may have an alterable refractive index. Theelectro-active element may be disposed between electrodes (e.g. shown inFIG. 3A, FIG. 3B, FIG. 5C, and FIG. 5D), which may be adapted forapplying power to the element. The electro-active lens 2 may include acontroller (e.g. shown in FIG. 3A, FIG. 3B, FIG. 5C, and. FIG. 5D),which may be electrically connected to the electro-active element, forexample, via the electrodes. The controller may be adapted forelectrically driving the electrodes for modulating the power applied tothe electro-active element. When power is applied to the element, forexample, above a predetermined threshold, the refractive index thereofis altered. The controller may include drive electronics, a power supplysuch as a rechargeable battery, and other elements for driving theelectrodes.

Referring again to FIG. 2A, the electro-active lens 2 may be a flexibleelectro-active lens including a flexible housing 4 and a flexibleelectro-active element 6 embedded in the housing. The flexible housingmay have a fixed optical power. The electro-active element may have anoptical power adapted for changing within an optical power range of froma minimum optical power to a maximum optical power. Electrodes 10 may beelectrically connected to the electro-active element for applying powerthereto. When power is applied to the element below a firstpredetermined threshold, the element may have the minimum optical power.When power is applied to the element above a second predeterminedthreshold, the element may have the maximum optical power. The fixedoptical power may be greater than the maximum optical power. In thisway, the fixed optical power may provide the majority of the opticalpower of the flexible electro-active lens.

In the present invention, for failsafe operation, when no power isapplied (e.g., across the electrodes), the loss in optical powerprovided by the electro-active element may be minimal. For example, thelens 2 may function as a static lens having a fixed optical power, forexample, adapted for correcting at either far, or alternatively atintermediate distance, or alternatively at near distance.

Referring to FIG. 1, FIG. 2A, FIG. 2B, FIG. 3A, and FIG. 3B, the housing4 may include an anterior film and a posterior film for containing theelectro-active element. For example, each of the films may beapproximately 100 microns thick and the electro-active lens may beapproximately less than or equal to 500 microns thick. Referring to FIG.2A and FIG. 3B the electro-active lens may be, for example,approximately less than or equal to 200 microns thick in the unfoldedstate. The unfolded electro-active lens may be, for example,approximately 9 mm wide and the folded electro-active lens may be forexample less than or equal to approximately 3 mm wide.

When used as a corneal inlay, the diameter of the electro-active lensshould not exceed the diameter of the cornea. In some embodiments of theinvention, the outer surface of the housing may be curved tosubstantially match the curvature of the cornea (when used in a cornealinlay) or the surface of the eye (when used in a contact lens).

FIG. 1 includes an example of the measures of a folded electro-activelens 2 in two dimensions. The horizontal dimension of a foldedelectro-active lens is preferable less than or equal to 2.8 mm, althoughother dimensions may be used.

Referring to FIG. 4A and FIG. 4B, the electro-active element may includemultiple individually activated liquid crystal layers for providingadditional optical powers between the minimum and maximum opticalpowers.

FIG. 3A and FIG. 3B show an expanded and collapsed view, respectively,of a flexible electro-active lens 2 in an unfolded state having asurface relief diffractive pattern and a liquid crystal layer inaccordance with another embodiment of the invention. The electro-activelens may be a flexible lens including a first flexible film 8 a having asurface relief diffractive pattern 20 that varies within a depth, d, asecond flexible film 8 b, a liquid crystal layer 22 havingelectro-active material 16, electrodes 10, a controller 12, electricalconnections 14, and alignment layers 18. The liquid crystal layer may bedisposed between the first and second films, which may form a flexiblehousing 8 for encasing the layer. The films may be composed of, forexample, polysulphones, polyetherimides, and/or other flexiblematerials.

The electrodes 10 may be electrically connected to the liquid crystallayer for applying power thereto. The controller 12 may be adapted forelectrically driving the electrodes for modulating the power applied tothe layer. The liquid crystal layer may have an alterable refractiveindex. When power is applied to the layer, for example, above apredetermined threshold, the refractive index thereof is altered.

The alignment layers 18 may orient the molecules of electro-activematerial 16 for providing an initial refractive index of the liquidcrystal layer 22 when power below a first predetermined threshold isapplied thereto. An electric field having power above a secondpredetermined threshold may be applied (e.g., across the electrodes) foraligning molecules of electro-active material for altering therefractive index of the liquid crystal layer.

The refractive index of the first and second films is typically fixed.In one example, the refractive index of the liquid crystal layer mayalternate between matching and mismatching the fixed refractive index ofthe first and second films.

In FIG. 3A and FIG. 3B, for failsafe operation, when no power is applied(e.g., across the electrodes), the liquid crystal layer may have (by wayof example only) a refractive index, n, (e.g., 1.67 and a thickness(e.g., less than 10 ?m) approximately equal to the surface reliefdiffractive pattern 20 of the film. In this embodiment the materialmaking up the surface relief diffractive also has a 1.67 index. When therefractive index of the liquid crystal layer matches the refractiveindex of the surface relief diffractive the electro-active lens willhave a negligible optical power. When the index of the liquid crystaldoes not match that of the diffractive material the electro-active lenswill have an optical power as that created by the diffractive pattern.

FIG. 4A shows the flexible electro-active lens 2 in a folded statehaving a plurality of electro-active layers and FIG. 4B shows theplurality of electro-active elements of FIG. 4A. In FIG. 4A, theelectro-active lens may include a flexible housing 4 having a fixedrefractive index, a plurality of electro-active elements 6 a, 6 b, 6 c,and 6 d embedded therein, for example, arranged in a stackedconfiguration, and electrodes 10 independently electrically connected toeach of the electro-active elements. In FIG. 4B, the electro-activeelements 6 a, 6 b, and 6 c may include layers of electro-active material16 separated by an insulatory material 24, such as, a flexibledielectric film. In FIG. 4A and FIG. 4B the electro-active elements maybe rigid, flexible, or less flexible than the housing.

In FIG. 4A and FIG. 4B each of the electro-active elements may have analterable refractive index and may be individually activated. Since eachelectro-active element is insulated from one another it is possible toselectively or in any combination turn on an electro-active element orelements. By doing this it is possible to have an additive combinationof optical powers or provide for a single optical power. This allows forthe ability to tune the optical power of the lens or optic comprisingsuch an optically stacked multiple layer of electro-active elements postsurgical implantation.

The electro-active elements may be activated in response to a controlsignal from a source external to the electro-active lens. Referring toFIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D, the electro-active lens mayinclude a receiver, such as, sensing device and/or a memory metal, forreceive control signals from a source external to the lens. The controlsignals may be used to modulate the power applied to each of theelements for remotely tuning the optical power thereof.

Referring again to FIG. 4A and FIG. 4B, the electro-active elements maybe stacked and may be individually activated for altering the totaloptical power of the electro-active lens in any combination of thealterable optical powers of the elements.

In FIG. 4B the electro-active lens includes electro-active elements 6 a,6 b, and 6 c that, when activated, have exemplary optical powers of+0.25D or −0.25D, +0.50D or −0.50D, and +2.50D or +1.25D, respectively.For example, the elements may be activated in various combinations forproviding a total optical power in a range of from a minimum opticalpower of +0.25D or −0.25D by way of example only, by activating only a+0.25D or and a −0.25D which ever is needed to a maximum optical powerof +4.50D by way of example only, by activating a combination of a +25D,a +50D, a +2.50D, and a +1.25D. In this example, the electro-active lensmay have optical powers in each increment of 0.25D (positive ornegative) between the minimum and maximum powers. When each of theelements is individually activated in suitable combinations, the elementmay provide an increment of change in optical power and the totaloptical power of the electro-active lens may be tuned to desired opticalpowers. The increment of change in optical power in this example is0.25D, but in certain other embodiments it is 0.12D. The elements may beadapted for providing correction for near, intermediate, and/or fardistance viewing. It may be appreciated that the values used herein areintended for demonstration and different optical powers, increments ofchange in optical power, and/or numbers of the electro-active elements(e.g., limited in size for fitting the eye) may be used.

In the present invention, one or more of the elements 6 c may bepixilated. The electrodes may apply power to the pixilated elements. Byshunting certain electrodes it is possible to provide approximately 50%of the maximum optical power of the elements. In the example above,element 6 c may provide a maximum optical power of +2.50D and a 50%reduced optical power of +1.25D.

One or more of the electro-active elements may comprise a modal element.Modal elements may change optical power when an electrical potentialgradient is applied to a variable focus modal lens. Modal elements cancreate a refractive optic using, for example, liquid crystal.

Referring again to FIG. 4A and FIG. 4B, the electro-active elements 6 a,6 b, 6 c, and 6 d may include a combination of polymer dispersed liquidcrystals and bi-stable liquid crystals. When sufficient power is appliedto each of the elements (e.g., across the electrodes) the bi-stablecrystals may be tuned for achieving a desired optical power while thepolymer dispersed liquid crystals may be remotely cured or fixed withinthe element once the desired optical power is set. Curing the crystalsmay fix the orientation of the molecules for securing the tuned opticalpower while the electro-active lens is positioned or embedded in theeye. An electro-magnetic signal (e.g., a laser) having an eye-safewavelength(s) (e.g., 1.5 ?m wavelength) may be used for remotely curingthe crystals, for example, using an initiator that is sensitive to thewavelength(s) of the electro-magnetic signal. Polymer dispersed liquidcrystals may include, for example, a mixture of a nematic liquid crystalmixture E7 (produced by Merck) and a UV cured optical adhesive NOA65(produced by Norland Products). In one embodiment, the bi-stable liquidcrystal may be remotely tuned and the polymer may be remotely curedusing devices positioned external to the eye, while the electro-activelens is embedded within the eye.

Bi-stable liquid crystal material may be used to reduce the amount ofelectrical power consumption required over time to power theelectro-active lens. Upon application of an appropriate first voltageabove a first predetermined threshold, the overall orientation of theeach of the individual bi-stable liquid crystals may retain anorientation induced by the first voltage once the voltage is removed.They may be returned to their original state by applying a secondvoltage below a second predetermined threshold. Bi-stable liquidcrystals may include, for example, surface stabilized ferroelectricliquid crystal (SSFLF), which is a smectic liquid crystal. The use of abi-stable liquid crystal may reduce electrical power consumption,because voltage may be used to just switch the device between its statesand typically not to maintain the states of operation.

FIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D, each show a front view of aflexible electro-active lens 2 having a flexible electro-active element6. The flexible electro-active lens includes a flexible film 4 in whichthe electro-active element is embedded, a power source 26, electrodes 10and a memory metal material 28. The memory metal material may bias theelectro-active lens into its unfolded state. For example, theelectro-active lens may be folded for inserting into an incision in theeye. Once the electro-active lens is released within the eye, the memorymetal material may unfold the lens into its unfolded state for operationwithin the eye.

Referring to FIG. 5C and FIG. 5D, the electro-active lens may include acontroller and/or drive electronics 12 and electrical connections 14.

The electrodes 10 may be electrically connected to the electro-activeelement for applying power thereto. Referring to FIG. 3A, at least oneof the electrodes may form a relief pattern, conforming to the surfacerelief diffractive pattern 20 of the first film 8 a.

Referring again to FIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D, theelectrodes may include a plurality of concentric electrode rings. Whenthe electrodes apply electrical power to the electro-active elementhaving such rings, the element may thereby be provided with diffractiveoptical properties.

In the present invention, the electrodes may be switched on and off inless than approximately one (1) second. The electrodes may be composedof a conductive or metal material such as aluminum, an opticallytransparent material, such as, indium tin oxide (ITO), a conductiveorganic material, such as,poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate) (PEDOT:PSS)and/or carbon nano-tubes. The electrodes may coat and surround theliquid crystal material. The transparent material may include thintraces of metals such as silver or aluminum for increasing conductivity.Power may be applied across the transparent electrodes for alteringoptical properties of the electro-active lens, as described herein. Thethickness of the electrode layer may be, for example, less than 1 ?m butis preferably less than 0.1 ?m. The controller and/or drive electronics12, the power source 26, the memory metal material 28, and otherelectronic components may be connected to the electrodes by theelectrical connections 14. The electrical connections may include smallwires or traces, which may also be transparent. The electrodes andelectrical connections may be flexible.

Referring to FIG. 5B and FIG. 5D, the electro-active lens may include akinetic energy 50 electrically connected to the electro-active elementfor converting the motion of the eye into electrical power for providingthe electro-active element with the electrical power. The kinetic energydriver may include a conductor and permanent magnets located within thedriver. When the conductor moves relative to a magnetic field producedby the permanent magnets, electrical power is generated. Such driversare well known in the art and are typically used for non-battery poweredwrist watches. For example, eye movements such as rapid eye movements(REM) may charge the power source 26 (e.g., during sleep and/or wakecycles).

Referring to FIG. 5A and FIG. 5B, the electro-active lens may includepiezo electric film 48 for generating electrical power. Thepiezo-electric film may be adapted for connecting the electro-activelens to an eye structure. The tension of the piezo-electric film may bechanged by the motion of the eye. The film may transduce the change intension into electrical power. For example, when the piezo-electric filmmay be attached to the ciliary body, iris, near or on the pupil, and asthe pupil dilates and/or constricts the piezo-electric film would bestretched and relaxed, thereby producing electrical power.

Referring to FIG. 5A and FIG. 5C, the electrical power may be generatedusing a photovoltaic cell of sensing device 32. The photovoltaic cellconverts solar power into electrical power as is known in the art. Thephotovoltaic cell may be adapted for charging using a 1.5 ?m infra-redlaser source (not shown), for example, positioned external to theelectro-active lens. The laser may, for example, be mounted on a pair ofspectacles adapted to recharge the power source when worn by a user.

In each of these embodiments, the electrical power generated may bestored within the power source 26. The power source may include abattery, such as a thin film battery, which may be rechargeable and/orflexible. The thin film battery may be inductively charged by remotecharging. In one embodiment a inductively enabled pillow (not shown)provides the inductive charge while the user of such an electro-activelens is sleeping.

In one embodiment, the memory metal material 28 may be used for biasingthe electro-active lens toward the unfolded state.

In another embodiment, the memory metal material may be used forreceiving control signals from a source external to the electro-activelens. The controller 12 may use the control signals for modulating powerapplied to the electro-active element. The memory metal material may beelectrically connected to the controller and the electro-active element.For example, the memory metal material may function as an antenna,capacitor, inductive coil or the like.

In another embodiment, the memory metal material may be used forcharging the power source 26. The memory material may form a coil and/oran antenna and may be adapted for inductively charging the power sourceusing electrical power transmitted wirelessly from a device external tothe electro-active lens.

In still another embodiment, the memory metal material may be used forprogramming and/or reprogramming the controller and/or driveelectronics.

The memory metal material may be composed of, for example,titanium-palladium-nickel, nickel-titanium-copper, Gold-cadmium,Iron-zinc-copper-aluminum, Titanium-niobium-aluminum,hafnium-titanium-nickel, nickel-titanium-copper, gold-cadmium,iron-zinc-copper-aluminum, nickel-titanium, and/oriron-manganese-silicon, or any combination thereof.

Referring again to FIG. 5A and FIG. 5C, the electro-active lens mayinclude a sensing device 32 for detecting sensory information. Thesensing device may include for example one or more of the followingdevices: a photovoltaic or UV sensitive photo cell, a tilt switch, alight sensor, a passive range-finding device, a time-of-flight rangefinding device, an eye tracker, a view detector which detects where auser may be viewing, an accelerometer, a proximity switch, a physicalswitch, a manual override control, a capacitive switch which switcheswhen a user touches the nose bridge or the like.

The sensing device may include two or more photo-detector arrays with afocusing lens placed over each array for measuring distances. A sum ofdifferences algorithm may be used to determine which array has thehighest contrast ratio for determining the distance in which an objectis placed from the electro-active lens.

The sensing device may include a range finder for detecting distancesfor focusing the electro-active lens and/or a solar cell for detectinglight ambient and/or incident to the electro-active lens.

The sensing device may include a micro-electro-mechanical system (MEMS)gyroscope adapted for detecting head tilts or encyclorotation of theeye, an illustration of which is shown in FIG. 6. In addition, thesensing device may include a timing mechanism may be used in combinationwith the gyroscope for distinguishing a change in the distance viewedfrom the effects of bending over or other movements.

In response to the detection, the sensing device may trigger theactivation and/or deactivation of one or more of the aforementionedelements of the electro-active lens, for example, by altering theelectrical power applied thereto. The sensing device may be directly orindirectly coupled to the electronics and/or the electrical connectionsfor electrically driving the electrodes. In one embodiment, the sensingdevice may detect the focusing distance at which a user is viewing andmay alter or maintain the optical power of the electro-active elementaccordingly. In one example, if the sensing device detects that the useris focusing within the near distance range, the optical power of theelement may be altered so that the electro-active lens providescorrection for near distance viewing.

In the present invention, the electro-active lens may further include anover-riding remote switch (not shown) to manually over-ride and switchoptical states of the electro-active lens. For example, the remoteswitch may activate, deactivate, or set a desired optical power. Whenthe remote switch is activated, a remote switch signal may be sent tothe electro-active lens via an antenna formed from the memory metalmaterial 28.

Referring again to FIG. 5C and FIG. 5D, the electro-active lens mayinclude openings 34 for allowing nutrient and cellular waste productsproduced by the body to pass though the electro-active lens. Theopenings may be semi-permeable membranes that allow the passing ofmaterials therethrough based on the size of the material molecules. Theopenings and/or pores may be drilled, machined, or stamped. Typically,the openings and pores may be located at non-electrical or otherwisenon-critical areas of the electro-active lens such as near the pupillaryaxis where the electrodes do not extend or apply power. Such openingsare well known in the art with regards to non-electro-active cornealinlays.

FIG. 7A and FIG. 7B each show a front view of the flexibleelectro-active lens 2 having an axis A and a cross sectional view AA ofthe flexible electro-active lens 2 taken at the axis A. Theelectro-active lens includes a flexible film 4 and an electro-activeelement 6 embedded in the film. FIG. 7A includes an envelope 36,disposed between the flexible film and the electro-active element. Thus,the element is surrounded by the envelope, which is in turn surroundedby the flexible housing. The envelope may be a water repellent,protective barrier composed of, for example, hydrophilic acrylicmaterial. In one embodiment, the flexible housing may be composed of,for example, silicone or a hydrophobic acrylic material. Typically,hydrophilic acrylic materials have relatively low indices of refractionand are moderately rigid. Typically, hydrophobic acrylic materials haverelatively higher indices of refraction and are flexible.

The housing 4 may be composed of a semi-permeable membrane. The housingmay be coated with materials that are bio-compatible with anatomicalobjects in the eye. Bio-compatible materials may include, for example,polyvinyldene fluoride or non-hydrogel microporous perflouroether. Thehousing may optionally be coated with a sealer to prevent or retard theleaching of materials from the electro-active lens. The flexible housing4 may be a semi-permeable substance. The liquid crystal electro-activeelement and the associated electronics may be hermetically sealed forpreventing leaching out into the eye over time.

Referring again to FIG. 5A and FIG. 5B, the electro-active lens mayinclude haptics 30 for stabilizing the lens in a desired location withinthe eye as is well known in the art. The haptics may also include anantenna and/or recharging loops for receiving control signals from adevice external to the electro-active lens.

The electro-active lens may include intraocular lenses, which may beimplanted with the greatest possible centration (an alignment of acenter axis of the lens with a center axis or pupillary axis of the eye)to provide the best optical results. In a preferred embodiment of thepresent invention, the electro-active lens or a capsular bag housing theelectro-active lens should be implanted directly behind the pupil withthe greatest possible centration. The haptics 30 may be used to centerthe electro-active lens inside of the capsular bag. Alternately, thehaptics may be attached directly to the eye, for example, the ciliarymuscle, extending outside of the capsular bag. Because of anatomicalasymmetry in the eye, the electro-active lens may be implanted decentralto a pupillary axis. Additional decentration may be found within thecapsular bag (e.g., in a misalignment of a center axis of the capsularbag with a center axis of the electro-active lens inserted therein) andwith a misaligned pupil (having a curved or misaligned pupillary axis).The eye is typically tolerant of moderate amounts of decentration. Dueto anatomical asymmetry, a natural and unaltered eye may haveapproximately 0.1 or 0.2 mm of decentration. The electro-active lens maypreferably accommodate at least 1 mm of decentration

The electro-active lens may be implanted in an eye already having anexisting lens implant for correcting optical dysfunction provided by theexisting lens implant (not shown). This technique may be referred to as“piggyback” lens implantation. The electro-active lens may be implantedin front of the existing lens implant (e.g., closer to the exposedsurface of the eye), for example, into the posterior chamber in theciliary sulcus. In other embodiments, the electro-active lens may beimplanted behind the existing lens implant (e.g., farther from theexposed surface of the eye). In any of the above embodiments, theelectro-active lens may be used in combination with another, forexample, fixed crystalline lens. The lens may be positioned in theanterior or posterior chamber of the ciliary sulcus.

When embodiments described herein are used as a contact lens, the lensmay include an attached soft hydrophilic skirt at or near the lensperiphery for stabilizing the lens in a desired centrated position. Thecontact lens may further be stabilized by having a weighted orientingregion or a truncated attachment surface. The contact lens may beinductively charged by a contact lens case (not shown), for example,when the lens is located in the case. The sensing device 32 of thecontact lens (e.g., a photo-detector) may be located in or on thesurface of the contact lens or skirt attached, in a location spaced fromthe pupillary axis to not interfere with the vision of a wearer. In oneembodiment, the dimensions fitting parameters and/or components may becustomized according to the anatomical needs and/or preferences of auser.

FIG. 8A, FIG. 8B, and FIG. 8C, each show the placement of theelectro-active lens 2 in an eye 38 having different pupil sizes. FIG. 8Ashows a dilated pupil having a relatively large size. FIG. 8B shows apupil having a relatively moderate size. FIG. 8C shows a pupil having arelatively small size. FIG. 8A, FIG. 8B, and FIG. 8C, each show therelative locations of the pupil 40, the iris 42, the limbus 44, and thescelera 46, in the eye. The electro-active lens may include a flexiblehousing 4 and an electro-active element 6. As the size of the pupildecreased, the lens covers an increasing percentage of the pupil 40 oraperture of the eye.

In any of the above embodiments, liquid crystalline material may beused. Liquid crystals include a state of aggregation that isintermediate between the crystalline solid and the amorphous liquid.Many liquid crystals are composed of rod-like molecules, and classifiedbroadly as: nematic, cholesteric, and smectic.

The electro-active lens may be used to correct refractive errors of theeye including, presbyopia, myopia, hyperopia, astigmatism, andhigher-order aberrations.

When used herein, near viewing distance may describe distances from 18inches up to approximately 12 inches from a view point; intermediateviewing distance may describe distances from greater than 18 inches to29 inches and far viewing distance may describe distances greater thanapproximately 29 inches from ones face.

While the invention has been described with respect to a limited numberof embodiments, it will be appreciated that many variations,modifications and other applications of the invention may be made. Itwill be appreciated by persons skilled in the art that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the invention.

The invention claimed is:
 1. An ophthalmic system comprising: a baseoptic to provide a fixed base optical power, the base optic defining anoptical axis; a flexible electro-active element, disposed within thebase optic, to provide at least one of a variable optical power or avariable transmittance; a power supply, disposed within the base opticradially outward from the optical axis, to supply electrical power tothe flexible electro-active element; and a conductive coil, disposedwithin the base optic radially outward from the optical axis, to chargethe power supply via wireless charging, wherein the base optic comprisesa foldable intraocular optic and the conductive coil comprises a memorymetal material to unfold the base optic when the foldable intraocularoptic is implanted in an eye.
 2. The ophthalmic system of claim 1,wherein the base optic comprises at least one of a flexible intraocularlens, an intraocular optic, a contact lens, a corneal inlay, and acorneal onlay.
 3. The ophthalmic system of claim 1, wherein the flexibleelectro-active element comprises an electro-active material enclosedwithin a cavity formed by a flexible film.
 4. The ophthalmic system ofclaim 3, wherein the flexible electro-active element further comprises:a first electrode disposed within the cavity on a first side of theelectro-active material; and a second electrode disposed within thecavity on a second side of the electro-active material.
 5. Theophthalmic system of claim 3, wherein the flexible electro-activeelement further comprises a controller, disposed within the cavity, tocontrol the at least one of the variable optical power or the variabletransmittance of the flexible electro-active element.
 6. The ophthalmicsystem of claim 1, wherein the power supply comprises a ring-shapedpower supply disposed along an arc concentric with the optical axis. 7.The ophthalmic system of claim 6, wherein the conductive coil isconcentric with the ring-shaped power supply.
 8. The ophthalmic systemof claim 1, wherein the conductive coil is further configured as anantenna.
 9. A flexible ophthalmic lens comprising: a flexible film atleast partially defining a cavity; an electro-active material disposedwithin the cavity, the electro-active material having a variablerefractive index and/or a variable transmissivity; a first electrodedisposed within the cavity on a first side of the electro-activematerial; a second electrode disposed within the cavity on a second sideof the electro-active material; and a controller, disposed within thecavity electrically coupled to the first electrode and the secondelectrode, to apply power to the electro-active material so as to alterthe variable refractive index and/or the variable transmissivity of theelectro-active material.
 10. The flexible ophthalmic lens of claim 9,wherein the flexible ophthalmic lens is one of an intraocular lens,intraocular optic, contact lens, corneal inlay, and corneal onlay. 11.The flexible ophthalmic lens of claim 9, wherein the flexible filmcomprises a dielectric polymer.
 12. The flexible ophthalmic lens ofclaim 9, wherein the flexible film comprises at least one ofpolysulphone or polyetherimide.
 13. The flexible ophthalmic lens ofclaim 9, wherein the first electrode and the second electrode aretransparent.
 14. The flexible ophthalmic lens of claim 9, furthercomprising: a transparent electrical connection to electrically couplethe controller to the first electrode.
 15. The flexible ophthalmic lensof claim 9, wherein at least one of the first electrode and the secondelectrode comprises a ring-shaped electrode.
 16. The flexible ophthalmiclens of claim 9, further comprising: a base optic having a fixed opticalpower, wherein the flexible film is embedded within the base optic. 17.The flexible ophthalmic lens of claim 16, wherein the base optic is asflexible as the flexible film.
 18. The flexible ophthalmic lens of claim16 further comprising: a power supply, disposed within the base optic,to store the power applied to the electro-active material.
 19. Theflexible ophthalmic lens of claim 18, further comprising: a conductivecoil, operably coupled to the power supply, to wirelessly charge thepower supply.
 20. The flexible ophthalmic lens of claim 9, furthercomprising: an antenna, electrically coupled to the controller, toreceive a control signal via wireless communication.
 21. The flexibleophthalmic lens of claim 9, further comprising: a memory metal materialto bias the flexible ophthalmic lens toward an unfolded state.
 22. Aflexible electro-active lens comprising: a flexible housing having afixed optical power; a flexible electro-active element embedded in theflexible housing and having an optical power adapted for changing withinan optical power range of from a minimum optical power to a maximumoptical power smaller than the fixed optical power; and at least twophoto-detectors embedded in the flexible housing to sense incidentlight.
 23. The flexible electro-active lens of claim 22, wherein theflexible housing comprises a refractive optic.
 24. The flexibleelectro-active lens of claim 22, wherein the flexible electro-activeelement comprises a flexible film.
 25. The flexible electro-active lensof claim 24, wherein the flexible film comprises a dielectric polymer.26. The flexible electro-active lens of claim 24, wherein the flexiblefilm comprises at least one of polysulphone or polyetherimide.
 27. Theflexible electro-active lens of claim 22, wherein the flexibleelectro-active element is less flexible than the flexible housing. 28.The flexible electro-active lens of claim 22, wherein the flexibleelectro-active element is as flexible as the flexible housing.
 29. Theflexible electro-active lens of claim 22, wherein the at least twophoto-detectors are configured for use in determining a distance of anobject from the flexible electro-active lens.
 30. The flexibleelectro-active lens of claim 22, further comprising: a memory metalmaterial, embedded within the flexible housing, to bias the flexibleelectro-active lens toward an unfolded state.
 31. The flexibleelectro-active lens of claim 30, wherein the memory metal material isconfigured as at least one of: an antenna to receive a controlledsignal; or an inductive coil for inductive charging.
 32. The flexibleelectro-active lens of claim 22, further comprising: a coil, embeddedwithin the flexible housing, for wirelessly powering the flexibleelectro-active element and/or the at least two photo-detectors.
 33. Theflexible electro-active lens of claim 22, further comprising: aphotovoltaic cell, electrically connected to the flexible electro-activeelement, to provide power to the flexible electro-active element. 34.The flexible electro-active lens of claim 22, further comprising: akinetic energy driver, electrically connected to the flexibleelectro-active element, to convert motion of an eye into electricalpower for the flexible electro-active element.
 35. The flexibleelectro-active lens of claim 22, further comprising: a piezo-electricfilm, electrically connected to the flexible electro-active element, toconvert motion of an eye into electrical power for the flexibleelectro-active element.
 36. The flexible electro-active lens of claim22, further comprising: a concentric ring shaped electrode electricallyconnected to the flexible electro-active element.
 37. A flexibleelectro-active lens comprising: a flexible housing having a fixedoptical power; a flexible electro-active element embedded in saidhousing, wherein said flexible electro-active element has an opticalpower adapted for changing within an optical power range of from aminimum optical power to a maximum optical power, wherein said fixedoptical power is greater than said maximum optical power.
 38. Anophthalmic system comprising: a base optic to provide a fixed baseoptical power, the base optic defining an optical axis; a flexibleelectro-active element, disposed within the base optic, to provide atleast one of a variable optical power or a variable transmittance; apower supply, disposed within the base optic radially outward from theoptical axis, to supply electrical power to the flexible electro-activeelement; and a conductive coil, disposed within the base optic radiallyoutward from the optical axis, to charge the power supply via wirelesscharging, wherein the flexible electro-active element comprises: anelectro-active material enclosed within a cavity formed by a flexiblefilm; a first electrode disposed within the cavity on a first side ofthe electro-active material; and a second electrode disposed within thecavity on a second side of the electro-active material.
 39. Theophthalmic system of claim 30, wherein the base optic comprises at leastone of a flexible intraocular lens, an intraocular optic, a contactlens, a corneal inlay, and a corneal onlay.
 40. The ophthalmic system ofclaim 38, wherein the base optic comprises a foldable intraocular opticand the conductive coil comprises a memory metal material to unfold thebase optic when the foldable intraocular optic is implanted in an eye.41. The ophthalmic system of claim 38, wherein the flexibleelectro-active element further comprises a controller, disposed withinthe cavity, to control the at least one of the variable optical power orthe variable transmittance of the flexible electro-active element. 42.The ophthalmic system of claim 38, wherein the power supply comprises aring-shaped power supply disposed along an arc concentric with theoptical axis.
 43. The ophthalmic system of claim 42, wherein theconductive coil is concentric with the ring-shaped power supply.
 44. Theophthalmic system of claim 38, wherein the conductive coil is furtherconfigured as an antenna.